1. Field of the Invention
The present invention relates to an anti-mine system capable of effectively neutralizing buried mines, and in particular, to such a system which is readily portable and can easily positioned by small to medium scale robots to defeat buried anti-personnel.
2. Description of the Related Art
While buried land mines were first developed in the late 19th century and became widely used in WWI, during the early 20th century, an effective system to disable them has proven elusive—as the earth within which they are buried provides significant protection thereof. This difficulty in disabling such devices has been complicated with advances in the technology of the mines themselves; such as, blast resistant fusing, anti-handling features, and anti-tampering features.
In general, mine clearing, or breaching, during combat operations is conducted at a rapid operational tempo, and may be accomplished by using mine rollers or flails which either activate the mine's fuzing or damage the mine to the point where it will not function and detonate. Another option used has been to detonate bulk explosive charges on or over a known or potential minefield; which detonation creates a spike in pressure that is often sufficient to trigger a detoration of simple pressure fuzed mines. If the explosive charge is large enough, or is in sufficiently close proximity to the mine, the pressure spike may be sufficient to sympathetically decorate a mine. These techniques are usually employed over a broad area when individual mines' locations have not been identified. However, advances in mine technology have produced blast resistant mines; which have fuzes that are largely immune to being triggered by the brief pressure wave of a nearby bulk charge and require the more sustained pressure of a person or vehicle to detonate.
In non-combat situations, mine clearing is conducted at a slower tempo, primarily due to humanitarian concerns, such mine clearing is known as demining, and often involves the locating and neutralization of all individual mines in a given area. The most reliable approach to demining is to layout a search grid and manually probed each grid point to find all possible threats; however, this is very manpower intensive and time consuming. Alternative means of locating mines have been developed which are somewhat faster, such as using metal detectors and ground penetrating radar. However, such alternative detection equipment has a halo of uncertainty, wherein the mine itself may be within a given radius vs. the exact spot that the equipment is indicating. In general, within an approximately an 8 inch diameter circle about the detectors point of focus is considered a standard halo of uncertainty.
While the use of mine detection equipment greatly improved the rate at which demining could be accomplished, personnel still usually needed to remove the soil overfill material from over the mine to either manually disable the mine, or by any number of other means, including using a pyrotechnic torches, shaped charges or chemical means, disable the fuze or consume the explosive without it detonating. Or, alternatively, by simply placing a block of demolition charge in direct contact with the mine—trigger the fuze, or cause a sympathetic detonation of the explosive in the mine (and potentially other mines in the area—which may be dangerous to individuals in the vicinity). Further, these method's generally require the mine's footprint to be positively ascertained, since pyrotechnic torches, shaped charge, or chemical means generally have a single vector of attack, which is limited in cross-section. Also, the effectiveness of bulk charges in sympathetically detonating a mine greatly decreases with the distance from the mine—as the increased amount of overfill material dampens the pressure wave. However, the limits of current detection equipment do not allow the precise determination of the mine footprint; but, only the location of the mine within the 4 inch radius halo of uncertainty. Ensuring that a single vector defeat method contacts a buried mine within this halo is substantially more problematic in the case of small anti-personnel mines, which can be as small as 2 inches in diameter.
U.S. Pat. Nos. 6,298,763 and 7,182,011, utilize an explosively dart or plurality of darts that travel parallel to each other, downwardly to neutralize a mine. However, these darts in so traveling downwardly, perpendicular to face of the device, are limited in that they impact only a mine directly below the face of the device. Therefore, unless the device has a face large enough to cover the halo of uncertainty, or if the mine is located directly under the face—the device will fail to neutralize the mine.
An alternative anti-mine device is taught in U.S. Pat. No. 6,155,155. This device projects shattered fragments from a fragmentation component, to penetrate the overburden and neutralize the mines. However, such irregular fragments produced by such a device would not effectively penetrate the overfill/overburden, and the device would have to be very large and heavy—to realize the desired effect.
Robotic platforms, robots, have been increasingly deployed in demining operations to remove all humans from the danger zone. Increasingly, robots of this type have been created that are smaller and more portable. Due to the emergence of increased usage of such smaller robotics in the demining mission, a neutralization tool deployed from such a robot must not exceed its limited payload capability; but, still cover the halo of uncertainty.
Therefore, it can be seen that there is a need in the art for a device small and light enough to be utilized by small to medium scale robotic in demining operations; but, which has the penetrating power to penetrate the overfill and effectively and totally neutralize buried mines within the entire halo of uncertainty, even mines of the blast resistant variety.